As golfers have searched vainly for the perfect golf swing over the last 150 years in the history of this game, teachers and engineers have sought and designed teaching aids that hopefully will improve the golfer""s swing to hit the ball more consistently and further.
One such tool is a golf swing training system shown in the Ballard, et al., U.S. Pat. No. 5,050,885. The Ballard system includes a shoulder guiding device 122, 130, and 135 and a hip saddle 112 that straps around the pupil""s hip area. The thrust of the Ballard system is the provision of a lateral slide 90 on the base that permits the belt and the golfer""s hips to slide from two to six inches during the back swing, the down swing, and follow through. The slide 90 has a pair of rollers 87 and 88 that ride on a linear rail 61 that is parallel to the target line. Pivotal movement of the saddle is accommodated by a shaft 57 that permits the saddle to pivot about a horizontal axis perpendicular to the target line to accommodate the player""s tendency to raise one hip relative to the other. The sliding carriage is pivotally mounted on the base about a horizontal axis shown in FIG. 5, parallel to the target line and biased by a spring 51 that appears to accommodate the downward movement of the hips during the golf swing.
The slide 90 carries a first pivot 94, as seen in FIG. 9, upon which a link 99 is pivotal having another pivot 93 at its distal end to which the hip saddle 91 is connected. At the address position illustrated in FIG. 15, the slide 90 is positioned centrally on the rail 61 by springs 84 and 85, hip saddle 91 faces the ball, and the pivoting link 99 is parallel to the target line. During the back swing as depicted in FIG. 16, the slide 90 slides linearly away from the target compressing spring 84, and the belt pivots 45 degrees about the pivot 94, causing the user""s spine to shift backwardly a substantial distance rearwardly from the ball.
During the down swing, the belt pivot 93 and the slide 90 slide toward the target back to substantially the address position described above. Thereafter, during the follow through, the link 99 rotates counter-clockwise from its address position and actually throws the golfer toward the golf ball a substantial distance during the follow through. At the same time, the slide 90 compresses spring 85, causing a substantial lateral shift of the hips during the follow through compressing spring 85, as depicted in FIG. 17.
The lateral shifting of the saddle in the Ballard system during both the backswing and the downswing is not believed by most teaching professionals to be an appropriate teaching methodology.
The Remington, U.S. Pat. No. 1,530,519, shows a golf training apparatus designed to prevent any vertical or upward motion during golf swing. The golfer is restricted to pivoting his body around the fixed axis.
The Hara, U.S. Pat. No. 2,611,610, shows a mechanical system that holds the shoulders, hips and feet in position during the swing.
Another Hara, U.S. Pat. No. 2,755,091, shows a teaching device that restricts the golfer""s hip movement to rotary motion about a single axis, as does the device shown in the Abel, U.S. Pat. No. 3,429,571.
The Sheldon, U.S. Pat. No. 3,215,438, shows a hip training device for golfers that gives a warning signal when hip rotation departs from a single axis.
The Anselmo, et al., U.S. Pat. No. 4,593,909, has similar deficiencies to the Sheldon system.
The Jenks, U.S. Pat. Nos. 2,626,151, and 2,737,432, show golf training systems which coordinate body movement with some lateral movement of the hips.
The following patents also show swing training device as described in U.S. Pat. No. 5,984,797 referred to above.
The multiple pivot mechanism that connects the belt to the base inhibits lateral movement of the hips during the back swing and down swing. The belt is connected to the base by an expandable link pivotally connected at one end to the base and pivotally connected at its other end to the belt, both about generally vertical axes. As the golfer initiates the back swing, the belt pivots about the second axis as the link pivots in the opposite direction about the first axis. The link, as it rotates, expands somewhat as the spine travels in a clockwise arc about the pivot axis to the rear and inside of the right hip socket. As the golfer initiates the downswing, the link collapses and moves to a position almost parallel to the target line but somewhat outward from the address position. In the ball impact position, the link is collapsed between the belt and the base substantially parallel to the target line. The extension of the link during the backswing is what encourages the left hip to move clockwise and the spine to travel on the appropriate arc.
During the follow through, the link swings counter-clockwise allowing the right hip to move counter-clockwise and the spine to trace the appropriate arc which is an arc generally about the axis outside and to the rear of the left hip socket. After the follow through with the link collapsed and generally parallel to the target line, the golfer is encouraged to step forward toward the target by the expandable link which permits extension of the belt toward the target as the golfer takes an extra step with the rear leg over the forward leg toward the target encouraging an exceptional follow through.
In patent application, U.S. Ser. No. 09/440,846, Filed: Nov. 16, 1999, a golf swing training system is disclosed that guides the golfer""s hip rotation during the backswing and downswing and the follow through which, with repetition, enables the golfer""s muscle memory to repeat the desired hip rotation on the golf course without the training system. This hip rotation concept involves the pivotal motion of the hips during the backswing and downswing about a generally vertical axis behind and outside of the right hip socket(for right-handed golfers). During the follow through, the pivotal axis for the hips switches to a generally vertical axis outside and behind the left hip socket. This dual axis hip pivot automatically teaches the golfer the proper weight transfer from the right side to the left side.
Two of the principal advantages of that training system is that it eliminates undesirable hip sway and pivoting around a single axis that is taught in several prior swing training systems, such as the ones described in the Background of the Invention. Hip sway is the lateral or sliding movement of the hips in a plane parallel to the target linexe2x80x94and this motion is difficult for the golfer to control because the rear sway during the backswing requires a perfectly timed forward sway in the downswing to position the club properly at impact.
A further feature of that system is that it encourages without demanding the forward step of the rear leg over the forward leg after the follow through. This step teaches the golfer the proper total weight transfer to the left and is a valuable training tool. In fact, top professional golfers, such as present senior player Gary Player actually use this step while on the golf course.
Toward these ends, that golf swing training system includes a floor mounted base and a pelvic belt that wraps around the golfer""s hips and guides the golfer""s pivot during the backswing and follow through. The multiple pivot mechanism that connects the belt to the base inhibits lateral movement of the hips during the backswing and downswing. The belt is pivotally connected at a point B at one end to the base and pivotally connected at a point A at its other end to the belt, both about generally vertical aces. As the golfer initiates the backswing, the belt pivots about the axis (A) to approximately the limit of 45 deg. of turn as the right hip and spine travel in a clockwise arc(for right-handed golfers) about the pivot axis that is behind and outside of the right hip socket. At this point the movement is halted by a solid stop mechanism. As the golfer initiates the downswing, the hip belt pivots on axis (A) in the reverse direction back to its original square address position. Immediately, the initiation of the follow through begins with the second pivot point at axis (B), (a point on the outside and behind the left hip socket), allowing the golfer""s left hip and spine to move on an arc counterclockwise on that axis to a position facing the target and perpendicular to the target line.
Golf instructors use a variety of exercises to promote the development of the proper basic swing including having golfers execute a swing while standing with their buttocks up against a wall. This provides a demonstratable rear plane behind which no part of the golfer""s body or the club can cross during the backswing or follow through. As the machine controls the golfer""s motion, it promotes a simplified basic swing. This exaggerated exercise leaves the student with the xe2x80x9cfeelxe2x80x9d required to repeatedly execute his or her own individual swing with confidence when out of the machine. Previous training devices, including the parent of this C.I.P., do allow for the tracking of the right hip behind this critical back plane. The right hip is supposed to pivot but not move or change positions during the backswing. It is the left hip and spine that move on an arc around pivot point (A). The same holds true for the left hip during follow through when the right hip and spine pivot on an arc around point (B) on the left.
This system design, with the repositioning of the pivot points, the addition of the mechanical stops and the rigid construction of the mechanism, is what dictates that the hips and the spine travel on the appropriate paths.
Each of the first and second pivotal axes of the mechanism can be provided with an optional address biasing system. These address biasing systems are coil compression spring assemblies with an adjustable pre-load that are preset with the proper tension to assure that the belt assembly returns to the neutral position when at rest. Additionally, attached to the belt assembly and pivot block are opposing sets of tension posts; one central post on the top and bottom of the belt bar and multiple posts on the top and bottom of the support block slide mechanism. Tension bands or springs are positioned on these posts in combinations that provide resistance to the golfer""s initial pivot. This permits the instructor to adjust the swing resistance based upon the strength, size and ability of the pupil. The swing resistance created by this system not only builds muscles but with repetition, enhances muscle memory more than does a passive training system with no swing resistance.
Today, a major consideration of any device geared for public use, requires a commitment to facilitate both left-handed as well as right-handed participants. Previous devices either did not address this issue well or did not address it at all. A new, remarkably convenient conversion feature has been incorporated into this device allowing the system to be easily switched over without reduction of function from either side. The base mount block has been modified with a centrally positioned cylindrical hole into which a cylindrical xe2x80x9crotationxe2x80x9d shaft is inserted. This shaft is connected to the pivot that connects to and supports the hip belt mechanism. The converter xe2x80x9crotationxe2x80x9d shaft has a stop pin inserted in it that fits into a groove cut into and intersecting the cylindrical hole in the support block. When the belt mechanism is flipped over to perform the left-right conversion, this pin acts as a positioning stop to keep the belt mechanism level on either side. The mechanism is secured in position by a mechanical pressure locking pin inserted into a hole drilled in the top of the block down into a corresponding pre-positioned hole in the rotation shaft.
Another object of that swing trainer is to achieve a compact swing of the type institutionalized by the swing of Gene Sarazen. That swing is characterized by a full hip turn in the backswing but not more than 45 degrees, a substantial weight shift to the right foot in the backswing without a significant lateral shifting of the hips, a downswing initiated by the lower legs with the hips moving back toward the address position, an impact position with the lower body not leading the upper body significantly in contra-distinction to the Johnny Miller reverse xe2x80x9cCxe2x80x9d position at impact, with the body generally upright and the shoulders remaining generally horizontal and a compact follow through with the hips facing the target and the hands flowing up and over the head again with the shoulders mainly horizontal.
The U.S. Ser. No. 09/440,846 system achieves these results in part by providing a rigid lateral link between the first pivot and the base to prevent free sliding lateral movement of the belt. Next, the dual pivot positioning permits the free rotational movement of the belt during the backswing and downswing and follow through permitting the golfer""s spine to move on the desired arcs. Each of these freedom of movement features are not without limits and while the golfer is permitted some freedom of movement, he or she is still restricted by the mechanical limits of the system; otherwise, the training device would have no purpose.
One of the inventors, Stephanie Kossnar, has been playing golf and delivering golf instruction for over 37 years. She has been involved in training, development of training products, and technical writing for 30 years. Working as a golf instructor for the last 4 years, she has found that the two generally held theories of the golf swing do not explain the actual (or correct) movement of the body during the swing. The first of these concepts is rotating around a central axis during the swing, and the second is where the hips make a lateral movement preceding the rotation for the backswing and the rotation for the downswing.
Because the lower body is the foundation of the swing, and the lower body has two support points (the left leg and the right leg), Stephanie""s concept of the swing purports that there are two points of rotation, or axes, in the swing. One of these points is for the backswing and downswing motion and the second for the follow-through. In each rotation, the spine moves on an arc originating about the two axes described above.
During the backswing, the mechanism allows the golfer""s weight to be transferred to the inside of the right leg as the spine moves on an arc around the first axis point. The rigid belt holds the golfer""s hips in a level position. This discourages a reverse pivot (the weight shifting on the left leg instead of the right). Because the movement of the spine on the arc of the first axis discourages both a lateral movement and a rotation of the hips around a center axis, this movement xe2x80x9cpullsxe2x80x9d the weight off the left side and onto the right. This also prohibits a reverse pivot.
The position of pivot A allows the left hip to continue on an arc that allows the hips to rotate to 40-45 degrees depending upon the flexibility of the golfer. The proper location of the first axis pivot point restricts the right hip from rotating back beyond the swing/target line of the two axes at the address position. This restriction prevents sway of the lower body. (Sway is defined as an excessive weight shift to the outside of the right leg and foot in a right-handed golfer""s backswing that prevents the proper shift back to the left during the downswing). Previous center-axis or lateral-hip-movement training devices allow or encourage sway.
During the downswing, the golfer""s spine returns obstensibly to the original stance position. The weight then shifts to the forward or left side, and the second axis defines a new arc formed by the radius between the second axis and the spine. The spine travels along this new arc toward the target until the golfer""s body is facing the target on a line perpendicular to the target line.
At this point the golfer""s momentum is allowed to continue traveling off the arc toward the target, and he may take a step over to maintain balance.
The golf training apparatus of the present invention virtually demands that the golfer accurately execute these series of steps that make up Stephanie""s concept of the golf swing.
In contrast to the system in U.S. Pat. No. 5,984,797, the Continuation-in-Part application, U.S. Ser. No. 09/440,846, includes the repositioning of the two pivot points and the adjustability of the distance between the two pivot points.
In a right handed golfer, the right(back) pivot is now positioned directly to the outside right rear of the right hip joint. The left(front) pivot is adjustable and can and should be positioned to the outside left rear of the left hip joint.
The rear-most corner hinge section of the belt assembly has been repositioned to correspond to the centerline of the rear pivot point(point A). The pivot points should not be mounted any further back from the belt assembly than is mechanically feasible. This acts to keep the hips in front of or on the proper swing/target line during the backswing.
The forward pivot point is moved relative to the pivot bar until it is properly positioned relative to the left (front) hip and then locked in place with the pivot bar lock. This allows for the hips to remain on the swing/target line during follow through. This adjustability feature accommodates various body types and hip structures.
The proper positioning of the pivots in this new assembly eliminates the need for the slide mechanism that functioned as compensation for the pivot points in the parent application.
The slide component and the original position of the pivots allowed the proper swing to be executed with close professional guidance. This mechanism, however, also allowed the user to make moves by not adequately controlling or limiting the user""s movements.
Prior to adjusting the pivot centers, several other adjustments are advised. First is the height adjustment to bring the belt assembly to a proper position on the user""s hips. Second is the belt width adjustment to assure a secure fit on various body types and sizes.
Another; adjustment feature in Continuation-in-part, U.S. Ser. No. 09/440,846, is a positioning screw that allows the upright support bar of the base to be held in a generally vertical, or slightly forward of vertical, position. This adjustment accommodates the individuality of the user""s stances. (This feature eliminates the need for certain components, such as springs, cords or shock absorbers, inside the relatively inaccessible bottom-most housing section of the post assembly).
The springs inside the topmost housing of the post assembly provide,adequate give to allow proper freedom of movement during setup of the address position by the golfers.
Several new mechanical stops have been added to the pivot mechanism that further enhance the function of the new dual-pivot configuration. They act to further control or limit the range of motion possible while using the mechanism.
The first, outside of the rear pivot, limits the belt assembly to a 45 degree motion(turn) during the backswing by contacting the pivot mount which is attached at a 45 degree angle to the pivot hinge on the belt assembly.
The second stop is on the other side of this pivot mount and squares the belt assembly at set-up and also prevents the belt assembly from going back beyond the original on-line position during the downswing.
Additional stops have been added to both sides of the base mounting block to properly position the pivot arm attached to the front pivot assembly. They assure that the belt stays parallel to the swing/target line during the set-up and,rest positions.
Further enhancing the machine""s effectiveness is a tension adjustment feature. The belt and pivot grip assemblies have been fitted with a set of pins, both above and below, one on a belt bracket (approximately at the rear pivot point) and several (three as an example) on the pivot arm saddle at varying distances from the center pin.
Through repeated use, this enhancement promotes the user""s strength and muscle memory in a physical therapy or rehabilitation function. By attaching one band from the center pin, three different tension positions are possible. By using two bands in tandem from the center pin to the other pins the various combinations of attachment will provide six distinct tension levels.
In accordance with the present invention, an improved freestanding golf swing training system is provided with a floor-mounted base and a pelvic belt assembly that wraps around the golfer""s hips and guides the golfer""s pivot during the backswing, downswing and follow through.
This new system is philosophically the same as in parent application, U.S. Ser. No. 09/440,846, Filed: Nov. 16, 1999, but contains many structural improvements that enhance. performance, manufacturing, and comfort, as well as safety.
As in U.S. Ser. No. 09/440,846, an adjustable dual axis system is provided that guides the pelvis as it pivots about an axis behind the right leg in the backswing and downswing, and pivots about an axis behind and outside the left leg in the follow through.
The mechanism allows the distance between the pivot centers to be adjustable to various hip sizes, but the belt width is no longer adjustable at its rear because belt flexibility has been increased.
Instead of steps to limit movement about the two pivot axes, arcuate slotted plate and pin assemblies provide improved performance and safety.
The pivotal movement of the columnar base in a vertical plane has been eliminated and replaced with a horizontal pivot in the plane of the belt assembly that accommodates pelvic tilt at address in a far simpler fashion. The rigidity of the base has been improved with three tubular vertical rod supports triangularly arranged and connected together at their bottoms and tops by aluminum extrusions. An additional aluminum extrusion defines a slide on the rod supports and a column head that in turn supports a pivoting slide on the belt assembly.
The pivoting slide is now defined by a pair of rods that define the ways for the belt assembly slide and a separate tension slide. With the tension slide independent of the belt assembly slide, a wide range of neutral tension adjustments may be made.
Rather than providing a plurality of different size cushions on that belt assembly, all cushions are identical to one another and cast or laminated into a composite of different durometer layers for improved belt comfort.
Other objects and advantages will appear more clearly from the following detailed description.